Automatic circuit-controller.



No. 662,480. Patented Nov. 27, I900. a. H. WHITTINGHAM.

AUTOMATIC CIRCUIT CONTROLLER.

(Application filed Mar. 19, 1900.)

(N 0 ll ad a l UNITED STATES enoncn H. wnrrTINenAM,

PATENT @FFICE.

OF BALTIMORE, MARYLAND.

AUTOMATIC CIRCUIT-CONTRDLLER.

SPECIFICATION forming part of Letters Patent N 0. 662,480, dated November 27, 1900.

Application filed March 19, 1900. Serial No. 9,206. (No model.)

To aZZ whom it may concern:

Be it known that I, GEORGE H. WHITTING- HAM, a citizen of the United States, residing at Baltimore, in the State of Maryland, have invented certain new and useful Improvements in Automatic Circuit-Controllers, of which the following is a full, clear, and exact description.

This inven tion relates to automatic circuitconirollers, the object being to provide means for closing and opening a circuit automatically as necessity arises and for accomplishing this by means whereby a predetermined inactive period may be caused to elapse between the moments of opening and closing the circuit. For instance, in driving an electric pump to compress air or gas a circuitcontroller for the pump, which acts automatically in response to the pressure of the air or gas, ordinarily opens the circuit when the pressure reaches the maximum and immediately closes it if a reduction of pressure takes place even to a very slight degree. In a system in which the pressure is rapidly utilized such a circuit-controller would be almost constantly vibrating at the contacts; and it is the object of my invention to provide a circuit-controller which after opening the-circuit when the maximum pressure is reached will hold it open until the pressure is diminished to a predetermined extent,- whereupon the circuit is closed and the pressure again augmented.

In describing myinvention I have assumed, for example, a system in which an electric motor is used to drive a pump to compress or force the air or gas into a tank and have equipped a pressure-gage which connects with the tank with two cut-outs which are adjusted to act successively upon two circuits shunting the main circuit-controller. One of these shunt-circuits is provided with asecond cut-out operated by the main circuit-controller. While either of these shunts is closed the main circuit-controller is deenergized and the cousumption-circuit intact. The shunt containing the two cut-outs being the last one to be opened at the gage will when opened cause the main circuit-controller to be energized, which will thereupon make a second break in said shunt and open the consumptl011-0l1(311lt. If now the said shunt closes at the gage, it willstill remain open at the second cut-out and the main circuit-controller will not be deenergized until the first shunt containing the single cut-out at the gage is closed.

In the accompanying drawing the figure is a diagrammatical representation of the circuits and apparatus necessary to illustrate my invention.

Referring to the drawing by letters and figures, A and B respectivelyindicate supplymains, across which is connected a circuit (t1), supplying an electric motor or other translating device, which motor we will assume operates a pump to store air or gas in a tank. G indicates a pressure-gage subjected to the pressure in said tank.

D is an electromagnet in the form of a solenoid whose core 3 carries a bridging conductors, adapted to connect and disconnect two contacts 0 and c in the motor-circuit a b. The solenoid is for convenience connected across mains A l3 in a circuit 1 2, containing suitable resistance R.

Referring again to the gage G, it will be seen to consist of a curved tube g, to the free ends of which are hinged two arms '2' and j, respectively, which are adapted to connectand disconnect with contacts t" and j, respectively. Two springs 23 and p are attached at one end to a post q and at their other ends, respectively, to the two arms z" and j, tending to hold said arms against their contacts. Two adjusting-screws r and 9", working in a post r bear against the arms 2' and and serve as fulcrums, upon which said-arms will turn when the curved tube g straightens or fiexes by reason of a variation of pressure therein.

From the wire 1 a shunt circuit leads around the solenoid by way of wire 3, post (1, spring 1), arm j, contactj, and wire at to wire 2. A second sh unt around the solenoid leads by wire 8, post q, spring p, arm 2', contact 1', wire 5, and across the contacts 0' and c to wire 2, and thus contains two cut-out points.

The operation is as follows: Let us assume, for illustration, that the allowed variation of pressure in the tank is five pounds, which means that the adjusting-screws r and 1" are set so that the pressure may vary within the limits of five pounds before both of the arms t' and 7' will connect with or disconnect from their contacts. Let us also assume that the pressure for the present is at or below the minimum side of the five pounds, under which condition both arms iandj are against their respective contacts, the contacts 0 and c being bridged and the motor running. hen the pressure rises beyond the minimum side of the five-pound limit, the straightening of tube g causes the armj to break connection withits contact and open the shunt-circuit 3 et. This will make no change in the condition of the system, since the current will still have a path around the solenoid through the shunt-circuit, and the motor will continue. When the pressure rises to the maximum side of the five-pound limit, the armt' will leave its contact and open the second shunt-circuit, thus causing current to flow through the solenoid, which thereupon lifts its armature and opens the circuit of the motor across the contacts 0 and c and at the same time makes a second opening in the second shunt. Now if the pressure immediately lowers, the arm t' at once renews its connection with contact 2'; but the shunt which this connection formerly opened is not now closed thereby, because of the opening at c 0 The result is that the pressure may continue to lower to the minimum side of the 'five-pound limit, at which point the arm j will connect with its contact and close shunt 3 4. The current will then flow over this shunt and avoid the solenoid, which becomes deenergized and allows its armature to fall and bridge the contacts 0 0 whereupon the motor again starts. This arrangement of two shunts around the circuit-controller, with a cut-out in each and a second cut-out in one of them, therefore insures a positive action of the main circuit-controller and affords means for predetermining the period of inactivity of the circuit-controller.

The interval of inactivity of the main solenoid may be adjusted from zero to any desired maximum by simply setting the screws r and r.

Having described my invention, I claim-- 1. The combination with a circuit controller of two sh un t-ci-rcuits around the same, a cut-out in each shunt, one of which is operated by the circuit-controller, substantially as described.

2. The combination with a circuit controller of two shunt-circuits around the same,

one shunt-circuit containing one cut-out and the other containing two cut-outs, substantially as described.

3. The combination with a circuit controller of two shunt-circuits around the same, one shunt-circuit containing one cut-out and the other containing two cut-outs, one of the latter being operated by the circuit controller.

4E. The combination with a circuit controller, of two shunt circuits around the same, one shunt-circuit containing one cutout and the other containing two cut-outs, and a adapted to operate one cut-out in each shuntcircuit,substantially as described.

, 5. The combination with a circuitcontroller, of two sh nut-circuits around the same, one shunt-circuit containing one cut-out and the other containing two cut-outs, and a gage adapted to operate successively one cut-out in each shunt-circuit, substantially as described.

(S. The combination with a circuitcontroller, of two shunt-circuits around the same, one shunt-circuit containing one cut-out and the other containing two cut-outs, a gage adapted to operate one cut-out in each shuntcircuit and means for predetermining the interval between the operations of said cut-outs, substantially as described.

7. The combination with a circuit controller, of two shunt-circuits around the same, one shunt-circuit containing one cut-out and the other containing two cut-outs, one of the latter being operated by the circuit controller, a gage adapted to operate one cut-out in each shunt-circuit and means for predetermining the interval between the operation of said cut-outs, substantially as described.

8. The combination with a circuitcontroller, of a pressure-gage whose movable element is a curved tube, two arms hinged at one end to the free end of said tube, and at the other adapted to control respectively two circuits shunting said circuit-controller, and means for altering the angular relation of the arms, substantially as described.

In witness whereof I subscribe my signature in presence of two witnesses.

GEORGE H. WHITTINGHAM.

Witnesses:

WM. A. Rosnnsauzu, James A. DONNELLY. 

